Vane-type rotary engine

ABSTRACT

A rotary engine having the following construction. A rotor rotating in an elliptic cylinder is provided with four radial slots and a vane is slidably inserted through each of said slots with the root thereof pivotally connected to each apex of a quadrilateral linkage disposed in said cylinder. When the vane rotates while being carried by the rotor, the movement of the pivot point at the root of each vane is so regulated as to draw a common elliptical locus and, as a result, the tips of each vane moves while drawing a common elliptical locus. The inner peripheral surface of the cylinder in sliding engagement with the tip of each vane is shaped in an elliptical configuration conforming to the locus drawn by the tips of the vanes. By constructing as described above, the friction between the tip of each vane and the inner peripheral surface of the cylinder can be minimized and a stable high-speed running of the engine can be obtained.

United States Patent Inventor Akira Kobayashi Nagoya, Japan App]. No.36,130 Filed May 11, 1970 Patented Oct. 19, 1971 Assignee KabushikiKaisha Toyota Chuo Kenkyusho Aichi-ken, Japan Priority May 14, 1969Japan 44/37115 VANE-TYPE ROTARY ENGINE 1 Claim, 6 Drawing Figs.

U.S. Cl 418/253, 418/257, 418/270 Int. Cl. F0lc 1/00, F0lc 21/00 Fieldof Search 418/138, 241, 253, 262, 264, 270, 257; 123/8.45

References Cited UNITED STATES PATENTS 549,602 11/1895 Harding 418/253 X716,970 12/1902 Werner 418/270 X 3,196,854 7/1965 Novak 123/8453,369,529 2/1968 Jordan 418/270 X FOREIGN PATENTS 1,983 1868 GreatBritain 418/253 235,784 6/1925 Great Britain 418/253 PrimaryExaminer-Carlton R. Croyle Assistant ExaminerWilbur .l GoodlinlAttorney-Cushman, Darby & Cushman ABSTRACT: A rotary engine having thefollowing construction. A rotor rotating in an elliptic cylinder isprovided with four radial slots and a vane is slidably inserted througheach of said slots with the root thereof pivotally connected to eachapex of a quadrilateral linkage disposed] in said cylinder. when thevane rotates while being carried by the rotor, the movement of the pivotpoint at the root of each vane is so regulated as to draw a commonelliptical locus and, as a result, the tips of each vane moves whiledrawing a common elliptical locus. The inner peripheral surface of thecylinder in sliding engagement with the tip of each vane is shaped in anelliptical configuration conforming to the locus drawn by the tips ofthe vanes. By constructing as described above, the friction between thetip of each vane and the inner peripheral surface of the cylinder can beminimized and a stable high-speed running of the engine can be obtained.

PATENTEDum 191971 3,614,2 1?

sum 1 OF 5 INVENTOR fi/i/APH KOMWSH/ [ATTORNEYS PATENTEUDCT 19 I97! 3, 61 4 2 77 sum 2 or s INVENTOR BY v M ATTORNEYS PATENTEBUEI 19 mnINVENTORS 191/69 MMYflS/f/ BY Z0 M ATTORNEY:

PATfNTEnum 19 Ian SHEET M 0F 5 FIG". 5

INVENTOR HUM K061410314 BY i w A1 1 ORNEY PAIENTEIIIJCI 19 Ian SHEET 5BF 5 INVENTOR 14mm ummsg I MAJ .i

ATTORNEY 3 VANE-TYPE ROTARY ENGINE BACKGROUND OF THE INVENTION Thepresent invention relates to a vane-type rotary engine adapted for useas internal combustion engine, fluid motor, fluid pump, gas compressor,etc.

SUMMARY OF THE INVENTION The present invention provides a vane-typerotary engine which comprises four vanes disposed in an ellipticcylinder with one ends thereof pivotally connected to the apices of arhombic linkage respectively and rotating therein while being carried bya rotor, the rotational locus of the pivot point of each vane beingdefined by a cam having a cam surface on which a roller coaxial withsaid pivot point rolls and the configuration of which is so determinedthat the pivot points of said respective vanes will move along a commonpseudoelliptic path, wherefore the outer end surface of each vane drawsa locus of a point lying on an extension of the segment connecting apoint on said pseudoelliptic path with the axis of rotation of saidrotor and spaced from said axis of rotation of the rotor a distancewhich is the sum of the length of said segment and the length of saidvane, and the configuration of the inner peripheral surface of saidcylinder being determined in conformance with said locus, whereby thecentrifugal force acting on each vane is offset as a tension of therhombic linkage because said vane is pivotally connected to said rhombiclinkage, and hence the roller rolls on said cam in contact therewith atall times with a minimum contacting pressure and the friction betweenthe outer end surface and the inner peripheral surface of the cylinderis reduced to substantially zero; and which, therefore, is simple inconstruction, free of vibration and adapted for high-speed,high-pressure operation.

The present invention provides a rotary engine which can be used notonly as an internal combustion engine but also as a fluid motor, and canalso be operated as a fluid pump, a gas compressor, etc., by impartingan input to the drive shaft to discharge pressure fluid, and thus has avery wide range of application.

BRIEF DESCRIPTION OF T HE DRAWINGS DESCRIPTION OF THE PREFERREDEMBODIMENT First of all, the principle behind the present invention willbe explained with reference to FIG. 1. A rotor 2 driven by a drive shaft1 is mounted in a cylinder 3 and vanes 8, 9, l and 11 are insertedthrough radial slots 4, 5, 6 and 7 respectively which are formeddiametrically of said rotor. The inner ends of the vanes are pivotallyconnected to the pivotal connections of an equilateral quadrilaterallinkage (hereinafter referred to as rhombic linkage) L composed of links13, I4, and 16, respectively. The opposite links 13, 15 and l4, 16 ofthe rhombic linkage are respectively connected to each other at theircenters by support links 2] and 22 which are loosely mounted at theircentral portions on the drive shaft 1.

The rhombic linkage L rotates as the rotor 2 is rotated by the driveshaft 1. In this case, if the length of the diagonal of the rhombiclinkage contracts twice during one revolution of the rotor 1, due todeformation of said rhombic linkage, each vane makes an outward andinward movements twice diametrically of the rotor and the outer endsurface thereof draws an tion of the rhombic linkage is regulated insuch a manner that the outer end surface of each vane will draw commonlocus, and the configuration of the inner peripheral surface of thecylinder is determined in conformance with said common locus, a rotaryengine having two working chambers 34 and 35 between the outerperipheral surface of the rotor and the inner peripheral surface of thecylinder can be obtained.

For the outer end surface of each vane to draw the common locus, it isnecessary that the pivotpoint of the inner end of each vane draws acommon locus. To this end, rollers 27, 28, 29 and 30 are mounted onpivot pins by which the inner ends of the vanes are pivotally connectedto the rhombic linkage respectively, and a cam 31 is mounted on the endplates which has a cam surface to guide each roller in contact therewithat all times, when said roller moves incident to the rotation of thevane, in such a manner that the axis of said roller (the pivot pin ofsaid vane) will draw a common locus.

In the operation of the rotary engine constructed as described above,the centrifugal force acting on each wine is supported as components offorce along the rhombic linkage, and these components of force arecounteracted by the centrifugal forces acting on the adjacent vances andoffset as a tension of the rhombic linkage. Thus, the friction betweenthe inner peripheral surface of the cylinder and the outer end surfaceof each vane is reduced to substantially zero. Furthermore, the relativerotation between the drive shaft and the supporting links looselymounted thereon is decreased and the sliding speed of the vanes in therespective slots in the rotor is substantially lower than the speed ofthe piston in a piston engine and each vane is stable as it is supportedin said slot. Still further, the mechanism is very simple because thereciprocating movement of the vanes in the respective slots is effectedmerely by the roller-guiding cam, without using a special means.

The common locus drawn by the pivot points of the respective vanes isdetermined in the following manner: Namely, referring to FIG. 2 whichshows various shapes of deformation of the rhombic linkage, the maximumvalue of the half of the diagonal length p of the rhombic linkage isrepresented by a and the minimum value of the same by .b. The rhombiclinkage expands and contracts between the values a and b. Consideringthe supporting links which connect the centers of the opposite' linkswith each other, each of the supporting links makes an angular motionwith respect to the center of the rhombic linkage through an angle ofM0,, on both sides of a line at an angle of 45 to the vertical andhorizontal main axes (the perpendicular axial lines connecting theopposite ones of the four slots in the rotor). Each supporting link (thehalf of the length thereof being represented by r) rotates incident tothe rotation of the rotor, with each end thereof moving along acircumference of a radius r. However, since the rhombic linkage isrelatively fixed to the rotor, if an angular oscillation of :A0 isimparted to the rhombic linkage on each revolution of the rotor, thepivot point of each vane will draw an elliptical locus.

Then, a control mechanism as shown in FIG. 3 is assumed. Suppose that asun gear S having a radius 2r is fixedly mounted in concentricalrelation to the rotor and a planetary gear P having a radius r, rotatesin intermeshing engagement with said sun gear 8, with the axis thereofbeing supported on the rotor, as shown in FIG. 3. Since the sun gear andthe planetary gear are in relative motion, it is possible to considerthat the sun gear is rotated with the axis of the planetary gear beingfixed. ln this case, the point of projection on the horizontal diameterof the planetary gear of a pin at the outer end of a crank K having aradius R and rotating integrally with said planetary gear, makes ahorizontal motion of m. If a link G is provided extending from thecenter of the sun gear to pass the point of projection, said link willrepeat an angular motion of :A0, twice during one revolution of therotor, on both sides of a neutral point. This link corresponds to thevery supporting link of the rhombic linkage of the present invention. InFIG. 3,

elliptical locus. Therefore, if the expansion and the contracwhen therotor rotates through an angle of I the crank rotates through an angleof 24 and the supporting link is displaced through an angle A fromtheneutral position. In this case, the following relation isestablished:

and thus the relation between the rotational angle D of the rotor andthe angular displacement A0 of the supporting link from its neutralposition is regulated.

On the other hand, when the rhombic linkage is square in shape, therelation of V. J l-b==2r 4 is established, while when the rhombiclinkage is in an intermediate position, the relation of p=2r cos (45+A0)(5) is established, whereby the value of the half p of the diagonal ofsaid rhombic linkage is determined. p is a or b when A0 is equal to A0,.Therefore,

p max a=2r cos (45-A0,,) (6) p min b=2r cos (45+A0,) and the ratiotherebetween is From equation (4), the value of b is calculated,considering that the radius of the rotor is I (the length of the vane) band the value of a is obtained by using a suitable design value for r.Then, the value of A0,, is determined from equation (7) and the angulardisplacement A0 of the supporting link, corresponding to the rotationalangle D of rotor is obtained from equation (1) and further the half p ofthe diagonal length of the rhombic linkage is calculated from equation(5) with respect to the rotational angle b of the rotor. Thus, the locusof the pivot point of each vane is determined.

For instance, when b=30 mm. and r=29 mm., a=49.64 mm. Then, when I=50mm., the radius of the rotor is 80 mm., i.e. l+b=80 mm., so that theminor and major diameters of the elliptical inner peripheral surface ofthe cylinder are 2(b+l )=160 mm. and 2(a+l)=99.64 mm. respectively. Thecam surface of the cam for guiding the rollers mounted on the pivot pinsfor the respective vanes is shaped to conform with the locus of a pointwhich lies on an extension of the segment connecting a point on thelocus described above with the center of the drive shaft and is spacedfrom said center of the drive shaft a distance which is the sum of thelength of said segment and the diameter of adid roller, where said camsurface contacts the outside face of each roller; and to conform withthe locus of a point which lies on said segment and is spaced from thepoint on said locus a distance corresponding to the diameter of theroller toward the center of the drive shaft, where the cam surface ofthe cam contacts the inside face of each roller.

In carrying out the present invention, the above-described linkmechanism is constructed as shown in FIG. 4 in which memberscorresponding to the respective. elements shown in FIG. 1 are indicatedby same numerals (and so are in the subsequent drawings).

A rotor 2 driven by a drive shaft 1 has four vane guide slots 4, 5, 6and 7 fonned in the cylindrical peripheral wall thereof radially indiametrical directions. Within the rotor 2 is provided a rhombic linkageL composed of links 13, 14, 15 and 16 of equal length pivotallyconnected with each other in sequence by pivot pins l7, l8, l9 and 20.The two pairs of the opposite links 13, 15 and 14, 16 are respectivelyconnected with each other by supporting links 21 and 22 which arepivotally connected to the centers of the respective links by pivot pins23, 25 and 24, 26 and which are loosely mounted on the drive shaft 1 attheir central portions. Vanes 8, 9, 10 and 11 of equal length areinserted through the slots 4, 5, 6 and 7 in the rotor 2, with the innerends thereof pivotally connected to the pivotal connections of therhombic linkage by the pivot pins respectively.

Rollers 27, 28, 29 and 30 of equal diameter are rotatably mounted on thepivot pins respectively. Further, a cam 31 having a cam surface as abovedescribed is mounted on the sideplates to regulate the movement of eachroller, rotating incident to the rotation of said rotor, in such amanner that the center of the pivot pin for said roller will draw acommon elliptical locus. By constructing as described above, the outerend face of each vane draws a common elliptical locus as described inthe explanation of the principle of the invention given previously, anda cylinder having an inner peripheral surface of a configurationconforming to said locus is provided. The tips of the vanes are providedwith spring-biased sealing members 81, 91, 101 and 111 respectively formaintaining sealing between the vanes and the inner peripheral surfaceof the cylinder even when the engine is subjected to shock. When thevane-type rotary engine is used, for example, as internal combustionengine, a fuel-air mixture injected into a working chamber 34 from anintake port 32 is carried therein while being compressed and, after thecompressed mixture is ignited and detonated by an ignition means 50, theexhaust gases are discharged from an exhaust port 33 through a workingchamber 35. F IG. 5 is a sectional view taken on the line VV of FIG. 4.The drive shaft 1 is fixed to opposite sidewalls 301 and 302, and therhombic linkage L, of the type shown in FIG. 4 is loosely mounted on thesubstantially central portion of said drive shaft 1. Further, rhombiclinkages L,, L of the same type are loosely mounted on the drive shaft 1on both sides of the rhombic linkage L The corresponding ends of theconstituent links of the respective linkages are connected with eachother by common pivot pins (e.g. pivot pins 17 and 19) and rollers arerotatably mounted on the opposite ends of said pivot pins (in the caseof illustration, rollers 271, 272 are mounted on the pivot pin 17 androllers 291, 292 on the pivot pin 19). The rollers 271 and 291 on oneends of the pivot pins are guided by a cam portion 311 projectinginwardly from the cylinder wall 322, while the rollers 272 and 292 onthe other ends of the pivot pins are guided by a cam portion 312projecting inwardly from another cylinder wall 322. Each of the oppositecam portions 311 and 312 has an elliptical cam surface which enables thecenter of each pivot pin to draw a common locus as stated previously.Further, each pivot pin (e.g. the pivot pin 17) has the inner end ofeach vane (e.g. the vane 8) pivotally connected thereto and the oppositeside edges of each vane are so shaped as to be held in close contactwith the inner surfaces 301 and 302 of the cylinder walls respectively.With the construction described, when each vane rotates incident to therotation of the rotor 2, each roller rolls on the cam surface whilebeing guided thereby and the rhombic linkages L L, and L connectedtogether by the common pivot pins, rotate synchronously while beingdeformed into the same shape. Therefore, each vane is carried by therotor with the outer end surface being held in sliding contact with theinner peripheral surface of the cylinder while moving inwardlyandoutwardly of the rotor through the slot formed in said rotor, incidentto the deformation of the linkage. In the embodiment shown, the rhombiclinkage L may be omitted but the use of three rhomic linkages isadvantageous in increasing the stability of the vanes.

In FIG. 6 there is shown an application of the present invention, inwhich two rotary machines A and B according to the present invention areconnected with each other side by side, using a common drive shaft, andare used as two-stage compressor by sending a gas, compressed in therotary machine A, into the rotary machine B to increase the finalcompression ratio. The linkages L,, L,, L and L are of the type shown inFIG. 4 and the constituent links of the respective linkages arepivotably supported by common pivot pins (e.g. pivot pins 17 and 19).Rollers mounted on the opposite ends of the respective pivot pins (e.g.rollers 271, 291 and 272, 292) roll on cams 311 and 312 projecting fromthe opposite cylinder walls 321 and 322 respectively, while being guidedthereby, and thus define the rotational locus of the linkages. In FIG.6, the members corresponding to the elements shown in FIGS. 4 and 5 areindicated by same numerals and descriptions thereof are omitted.

I claim:

1. A vane-type rotary engine comprising a cylinder, a drive shaftextending through said cylinder, a rotor mounted on said drive shaft tobe driven thereby and having four radial slots fonned therethrough inthe diametrical direction thereof, an equilateral quadrilateral linkageconsisting of four links of equal length pivotally connected with eachother in sequence by pivot pins and supporting links each having theopposite ends thereof pivotally connected to the centers of each of thetwo pairs of the opposite links, said supporting links being looselymounted on said drive shaft at the central portions thereof, four radialvanes slidably extending through said four slots in the rotor with theinner ends: thereof pivotally connected to said pivot pins respectively,rollers rotatably mounted on said pivot pins respectively and aninwardly projecting cam formed on the inner surface of said cylinder andhaving a cam surface which engages said rollers and regulates therotation of the same in such a manner that the pivot points of saidrespective vanes will draw a common locus as said vanes rotate incidentto the rotation ofsaid rotor, the configuration of the inner peripheralsurface of said cylinder being so selected as to conform to the locus ofa point which lies on an extension of the segment connecting a point onsaid common locus with the axis of rotation of said rotor and is spacedfrom said axis of rotation a distance which is the sum of the length ofsaid segment and the length of said vane from the pivot point to theouter end surface thereof.

1. A vane-type rotary engine comprising a cylinder, a drive shaftextending through said cylinder, a rotor mounted on said drive shaft tobe driven thereby and having four radial slots formed therethrough inthe diametrical direction thereof, an equilateral quadrilateral linkageconsisting of four links of equal length pivotally connected with eachother in sequence by pivot pins and supporting links each having theopposite ends thereof pivotally connected to the centers of each of thetwo pairs of the opposite links, said supporting links being looselymounted on said drive shaft at the central portions thereof, four radialvanes slidably extending through said four slots in the rotor with theinner ends thereof pivotally connected to said pivot pins respectively,rollers rotatably mounted on said pivot pins respectively and aninwardly projecting cam formed on the inner surface of said cylinder andhaving a cam surface which engages said rollers and regulates therotation of the same in such a manner that the Pivot points of saidrespective vanes will draw a common locus as said vanes rotate incidentto the rotation of said rotor, the configuration of the inner peripheralsurface of said cylinder being so selected as to conform to the locus ofa point which lies on an extension of the segment connecting a point onsaid common locus with the axis of rotation of said rotor and is spacedfrom said axis of rotation a distance which is the sum of the length ofsaid segment and the length of said vane from the pivot point to theouter end surface thereof.